Cholesterol is a waxy, fat-like substance produced by the liver. It builds healthy cell membranes, vitamin D, and certain hormones. Since it cannot dissolve in water, it does not travel through the bloodstream. It is carried by lipoproteins, which are low-density lipoproteins (LDLs, or bad cholesterol) and high-density lipoproteins (HDLs, or good cholesterol). High amounts of LDL or low amounts of HDL can lead to fatty buildup in the blood vessels. High cholesterol To find out one’s cholesterol levels, a lipid profile may be required. Here’s what the results mean: Total cholesterol in adults These are the parameters to check one’s total cholesterol: Normal: Less than 200 mg/dL Borderline: 200 to 239 mg/dL High: 240 mg/dL or above LDL cholesterol in adults These are the parameters to check one’s LDL cholesterol: Optimal: Less than 100 mg/dL Near-optimal: 100 to 129 mg/dL Borderline high: 130 to 159 mg/dL High: 160 to 189 mg/dL Very high: 190 mg/dL or above HDL cholesterol in adults These are the parameters to check one’s HDL cholesterol: Optimal: 60 mg/dL or higher Borderline: 40 to 59 mg/dL among men and 50 to 50 mg/dL among women Low: Under 40 mg/dL among men and under 50 mg/dL among women Medicare insurance covers routine blood checkups for high cholesterol once every five years.